The most important letters we possess of Sigmund Freud are the letters he wrote to his closest friend, the Berlin physician, Wm. Fliess, between 1887-1902, the time he was developing the science of psychoanalysis. In 1950, Marie Bonaparte, Ernst Kris and Anna Freud published approximately half of the letters. Pressure from the scientific world has been more or less constant since then for the publication of the entire correspondence. Miss Freud has at last agreed to this publication. I have been appointed editor, with Mrs. Lottie Newman and myself sharing the responsibility for the translation of the letters into English. Apart from the translation, my chief responsibility lies in writing a long introduction to the letters, and in writing a scholarly annotation to the letters themselves. Since large parts of each of the published letters were omitted in the original edition, I have decided, with Miss Freud's approval, to retranslate all the letters. I estimate that it will take approximately three years to complete this task. During that time it will be necessary for me to make several trips to Vienna to consult with other Freud scholars on the annotation and translation of the letters and to work in scientific libraries there. It will also be necessary for me to spend some time each year with Miss Freud going over the translation. I also plan to spend some time in the Library of Congress in Washington where the original letters are kept. The work is to be published by Basic Books in New York, with simultaneous publication German, with Fischer Verlag, and in France, Spain and Italy.